This article outlines the findings from a small-scale research study that explored how a group of secondary schools in challenging contexts had improved and raised attainment successively over a 5-year period. The study points to the importance of external factors and how they influence a school's ability to improve and to sustain improvement. The study also identified certain strategies for improvement that schools found to be successful in securing improved performance. The article argues that more highly differentiated improvement approaches to school improvement are needed for schools in such circumstances. It concludes by suggesting that while schools in challenging contexts can raise attainment and performance through their own efforts, the external environment remains an important influence upon a school's ability to improve.